Hi Griff -
If you're having crashing/saving issues here are a few troubleshooting steps you could try..
- Do a hard shutdown/restart of the computer
- Check to make sure that the startup disk is at least 20% empty
- Check to see that you have at last 8GB RAM (16GB would be preferable)
- Try saving to a different disk -- not being able to save could mean a disk is full or there's a permissions issue
- Check the versions of Logic, the OS, and the computer (model, year) -- always specify when posting an issue like this
- Reinstall Logic (if you have to update to do that make a zipped copy of the current version first in case you want to go back)
- Remove all 3rd-party plugins and try running Logic -- if problems go away, add them in 1-by-1 to see which is the cause